Appears 15 times in the Quran. (Root: ظنن)
  1. Then after sorrow He sent down security upon you, a calm coming upon a party of you, and (there was) another party whom their own souls had rendered anxious; they entertained about Allah thoughts of ignorance quite unjustly, saying: We have no hand in the affair. Say: Surely the affair is wholly (in the hands) of Allah. They conceal within their souls what they would not reveal to you. They say: Had we any hand in the affair, we would not have been slain here. Say: Had you remained in your houses, those for whom slaughter was ordained would certainly have gone forth to the places where they would be slain, and that Allah might test what was in your breasts and that He might purge what was in your hearts; and Allah knows what is in the breasts.

  2. And their saying: Surely we have killed the Messiah, Isa son of Marium, the messenger of Allah; and they did not kill him nor did they crucify him, but it appeared to them so (like Isa) and most surely those who differ therein are only in a doubt about it; they have no knowledge respecting it, but only follow a conjecture, and they killed him not for sure.

  3. And if you obey most of those in the earth, they will lead you astray from Allah's way; they follow but conjecture and they only lie.

  4. Those who are polytheists will say: If Allah had pleased we would not have associated (aught with Him) nor our fathers, nor would we have forbidden (to ourselves) anything; even so did those before them reject until they tasted Our punishment. Say: Have you any knowledge with you so you should bring it forth to us? You only follow a conjecture and you only tell lies.

  5. And most of them do not follow (anything) but conjecture; surely conjecture will not avail aught against the truth; surely Allah is cognizant of what they do.

  6. And what will be the thought of those who forge lies against Allah on the day of resurrection? Most surely Allah is the Lord of grace towards men, but most of them do not give thanks.

  7. Now, surely, whatever is in the heavens and whatever is in the earth is Allah's; and they do not (really) follow any associates, who call on others besides Allah; they do not follow (anything) but conjectures, and they only lie.

  8. When they came upon you from above you and from below you, and when the eyes turned dull, and the hearts rose up to the throats, and you began to think diverse thoughts of Allah.

  9. And We did not create the heaven and the earth and what is between them in vain; that is the opinion of those who disbelieve then woe to those who disbelieve on account of the fire.

  10. And when it was said, Surely the promise of Allah is true and as for the hour, there is no doubt about it, you said: We do not know what the hour is; we do not think (that it will come to pass) save a passing thought, and we are not at all sure.

  11. And (that) He may punish the hypocritical men and the hypocritical women, and the polytheistic men and the polytheistic women, the entertainers of evil thoughts about Allah. On them is the evil turn, and Allah is wroth with them and has cursed them and prepared hell for them, and evil is the resort.

  12. Nay! you rather thought that the Messenger and the believers would not return to their families ever, and that was made fairseeming to your hearts and you thought an evil thought and you were a people doomed to perish.

  13. O you who believe! avoid most of suspicion, for surely suspicion in some cases is a sin, and do not spy nor let some of you backbite others. Does one of you like to eat the flesh of his dead brother? But you abhor it; and be careful of (your duty to) Allah, surely Allah is Oft-returning (to mercy), Merciful.

  14. They are naught but names which you have named, you and your fathers; Allah has not sent for them any authority. They follow naught but conjecture and the low desires which (their) souls incline to; and certainly the guidance has come to them from their Lord.

  15. And they have no knowledge of it; they do not follow anything but conjecture, and surely conjecture does not avail against the truth at all.